1. Field of the Invention
The present invention relates to a location information providing technology. More particularly, the present invention relates to an apparatus and for tagging location information about a mobile device to a service request message which is transmitted to an application server for location-based services.
2. Description of the Related Art
A wireless communication system may provide a variety of location-based services using location information about a mobile device or a user. For example, it is possible to find locations near a user of the mobile device such as a parking place, a post office, a bus stop, a restaurant, a store, etc. given a user's current location. In addition, a map service or a navigation service may be provided considering a user's current location, and a local advertisement or event information may be offered depending on a user's current location.
Various approaches to the acquisition of a device location have been widely studied in the art. A mobile device having a Global Positioning System (GPS) module may obtain its location information from GPS satellites, and a mobile device having no GPS module may determine its current location by measuring a signal strength from a base station in a mobile communication network. Additionally, some applications may offer useful services to a user using only location information about a base station accessed by a mobile device. More particularly, in a recently emerging wireless communication network using femtocells or picocells, a spatial resolution between locations of a base station and a user is reduced to within several meters or tens of meters.
Generally, a server which obtains location information about mobile devices and provides it to others may be referred to as a LoCation Service server (hereinafter, an LCS server). In addition, an LCS client, which receives location information about devices from the LCS server and thereby provides location-based services to a user, may be referred to as an application server.
Location-based services, which are standardized in the 3rd Generation Partnership Project (3GPP) and the Open Mobile Alliance (OMA), depend on an LCS server. The application server transmits a location request message to the LCS server so as to request location information about a mobile device which is required for providing services to a user. The LCS server transmits a location response message to the application server so as to offer the required location information about the mobile device. In case of having no location information about the required device, the LCS server must refer to another LCS server or must perform procedures for determining a location of the user device. Unfortunately, this may often cause a serious delay in sending the location response message. Accordingly, there is a need for an improved apparatus and method for determining a location of a user device.